Search for dissertations about: "Hydroxypropyl cellulose"

Showing result 1 - 5 of 16 swedish dissertations containing the words Hydroxypropyl cellulose.

  2. 1. Mass Transport through Phase Separated Films - Effects of Ethyl Cellulose Molecular Weight on Cellulose Derivative Blends for Pharmaceutical Coatings

    Author : Helene Andersson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Coating; Ethyl cellulose; Diffusion; Mass transport; Solvent evaporation; Molecular weight; Phase separation; Film; Hydroxypropyl cellulose; Polymer blend; Cellulose derivatives; Controlled release;

    Abstract : Polymer blends are utilized for a variety of applications, not least in pharmaceutical coatings for controlled release of drugs. For instance, blends of ethyl cellulose (EC) and the water-soluble hydroxypropyl cellulose (HPC) can be used to coat drug pellets for oral extendedrelease formulations. READ MORE

  4. 2. Structure control by phase separation and influence on mass transport in films for controlled release

    Author : Helene Andersson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Controlled release; Coating; Cellulose derivatives; Hydroxypropyl cellulose; Solvent evaporation; Ethyl cellulose; Phase separation; Polymer blend; Molecular weight;

    Abstract : Controlled release coatings for oral pharmaceutics are often made of cellulose derivatives. Such coatings can be used to promote a prolonged therapeutic concentration in the blood by a slow drug delivery in the gastrointestinal tract. READ MORE

  5. 3. Foaming of Some Cellulose Derivatives - Initial Studies

    Author : Kristina Karlsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rheological characterisation; Foaming; hydroxypropyl methylcellulose HPMC ; scale-up production; ethyl hydroxyethyl cellulose EHEC ; hot-mould baking; cellulose derivatives; extrusion;

    Abstract : Fossil-based polymeric foams, based on polymers such as polystyrene and polyurethane, are important and widely employed materials due to their good mechanical properties relative their low density, the low price and the possibility for large-scale production. There are however a few disadvantages with these foamed products. READ MORE

  6. 4. Foaming of cellulose derivatives and hemicellulose-containing materials

    Author : Kristina Karlsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; β-glucan; arabinoxylan; scale-up production; hydroxypropyl methylcellulose HPMC ; ethyl hydroxyethyl cellulose EHEC ; hot-mould foaming; extensional viscosity; extrusion; hemicellulose; rheological characterisation; Foaming; xylan; cellulose derivatives;

    Abstract : Fossil-based polymeric foams are important materials due to their good mechanical properties relative their low density, the low price and the possibility for large-scale production. They are widely used in cushioning, absorbing and insulation applications. There are however a few disadvantages with these foamed products. READ MORE

  7. 5. Characterization of the Mechanisms of Drug Release from Polymer-Coated Formulations using Experiments and Modelling

    Author : Mariagrazia Marucci; Avdelningen för kemiteknik; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ethyl cellulose; Release mechanism; coating; polymer blend; modelling; ESPI; diffusion; osmotic pumping; SEM; single pellet; CLSM; hydroxypropyl cellulose; multiple-unit release;

    Abstract : The main objectives of the work presented in this thesis were to develop new experimental methods to improve the understanding of the release mechanism from a coated formulation and to develop new mechanistic models to describe the release process for pellets coated with a semi-permeable film. Another aim was to characterize the release mechanism from a formulation coated with films made of a blend of a water-insoluble polymer, ethyl cellulose (EC), and a water-soluble polymer, hydroxypropyl cellulose (HPC). READ MORE